The novel influenza H1N1 virus responsible for a world-wide pandemic throughout 2009 (H1N1(2009)) is expected to cause a second wave of infection during the 2009/10 winter season. Vaccines against H1N1(2009) will be available in early November, 2009. Adults with hematologic disorders are at high risk of influenza-related complications, including death. Given that the vaccination dosing for the pandemic vaccine has been developed on healthy individuals, it is unknown whether this subgroup of patients will respond similarly. We will evaluate the safety and efficacy of the pandemic vaccine in patients with lymphoid malignancies receiving active systemic treatment, or who have recently undergone stem cell transplantation. Patients will be randomized to one or two doses of the approved adjuvanted vaccine; immune responses will be measured to identify the optimal regimen. Also, we will look for an association between biomarkers of the immune system and a response to the vaccine; this will be done by measuring baseline CD3, 4, 8, 19, and 56 cells by flow cytometry.